The present invention relates to an information processing apparatus, an information recording medium, an information processing method and a computer program. More specifically, the present invention relates to an information processing apparatus, an information recording medium, an information processing method and a computer program which achieve storage of various contents for which contents utilization management is required and utilization management for each fragmented data unit.
Various kinds of software data (hereinafter, referred to as contents) such as audio data of music and so forth, image data of a movie and so forth, game programs, various application programs and so forth, can be stored as digital data on recording media such as Blu-ray discs for which a blue laser is used, DVDs (Digital Versatile Discs), MDs (Mini Discs) and CDs (Compact Discs). Particularly, the Blu-ray discs for which a blue laser is used allow high density recording and can record large capacity video contents and so forth as high picture quality data.
Such various information recording media have digital contents stored thereon and are provided as such to users. A user would use a reproduction apparatus such as a PC (Personal Computer) or a disc player to reproduce or utilize the contents.
With regard to many contents such as music data and image data, the distribution right or the like is usually owned by a producing person or a selling person of the contents. Accordingly, upon distribution of contents, fixed utilization limitations are typically applied. In particular, utilization of contents is permitted only to legal users so that a copy or the like of the contents may be prevented without permission.
Use of a digital recording apparatus and a digital recording medium allows repetitions of recording and reproduction, for example, without any deterioration in image and sound. This gives rise to a problem of a spread of distribution of illegal copy contents through the Internet, distribution of pirate edition discs which are CD-Rs and so forth on which contents are copied and utilization of copy contents stored on a hard disc for a PC.
Large capacity recording media such as a DVD or a recording medium for which a blue laser whose development has been, and is proceeding, is used to allow recording of a large amount of data corresponding, for example, to one or several movies as digital information on a single medium. As it becomes possible to record video information and so forth as digital information in this manner, it is a progressively significant subject to prevent illegal copying to protect the owner of the copyright. Recently, in order to prevent such illegal copying of digital data, various techniques for preventing illegal copying by digital recording apparatus and on digital recording media have been placed into practical use.
For example, a DVD player adopts a contents scramble system. According to the contents scramble system, video data, audio data or the like are recorded in an encrypted form on a DVD-ROM (Read Only Memory), and a key which is used to decrypt the encrypted data is provided to a licensed DVD player. The license is given to a DVD player designed so as to comply with predetermined operation prescriptions such as a prescription that no illegal copying is performed. Accordingly, the licensed DVD player can utilize the provided key to decrypt encrypted data recorded on a DVD-ROM to reproduce images and sound from the DVD-ROM.
On the other hand, a non-licensed DVD player cannot decrypt encrypted data recorded on the DVD-ROM because it does not have the key for decrypting the encrypted data. In this manner, according to the contents scramble system configuration, a DVD player which does not satisfy conditions required upon licensing cannot reproduce a DVD-ROM having digital data recorded thereon. As a result, illegal copying by the DVD player is prevented.
On the other hand, together with the popularization of a data communication network in recent years, a home network also is being spread. The home network interconnects various appliances, computers and other peripheral equipments so as to allow communication between the components. The home network provides convenience and comfortability to its user typically in that a data processing function is shared by the components through communication between the components, or contents are transmitted and received between the components. Thus, it is estimated that the home network is further popularized in the future.
As such networking proceeds, accessing to and utilization of stored contents on an information recording medium from and by an apparatus connected to a home network increases. The conventional illegal copying preventing system described above is typically based on the point of view that contents reproduction only by one licensed reproduction machine is permitted. Accordingly, sufficient consideration has not been yet taken to dealing with a process wherein an apparatus in which a recording medium is loaded among apparatus interconnected by a network, for example, a home server or a player, is accessed from another network-connected apparatus such as a PC or a television set so that contents of the recording medium are reproduced through the network.
Conventionally, such a form that utilization of one piece of contents stored in a recording medium is executed on a single reproduction apparatus is typically used. Therefore, it has been sufficient to set the right of use of contents such as a license to contents or a reproduction apparatus to perform utilization management of the contents. However, in the present age in which increase of the capacity of information recording media and digitalization and networking of apparatus in a home proceed, a utilization management configuration of contents different from that in the past is required. In particular, the following requirements are provided.
(1) Achievement of a configuration which records a variety of contents on a recording medium and allows utilization management which differs among different contents.
(2) Achievement of a contents utilization management configuration which allows utilization of contents within a particular network such as a home network; that is, contents reproduction by a network-connected apparatus or contents copying into a home server.
(3) Achievement of a configuration which distributes information necessary for contents reproduction through a network, for example, a key to be used for decryption of contents, to a particular user in safety.
It is, thus, desirable to achieve the configurations (1) to (3) above.